Answer
30.46 is the score after 2 years
Work Step by Step
The law of forgetting is given by this equation: $\log P = \log (P_{0}) - c \log (t+1)$
In the problem, it is given that c is 0.3, t is 24 months, and $P_{0}$ is 80
Thus $\log P = \log (80) - 0.3 \log (25)$
$\log P = \log (\frac{80}{25^{0.3}})$
$P = 30.46$
